Kaempferol Isolated from Nelumbo nucifera Inhibits Lipid Accumulation and Increases Fatty Acid Oxidation Signaling in Adipocytes

이봉기,권미성,최재수,Hyoung Oh Jeong,정해영,김형락 한국식품영양과학회 2015 Journal of medicinal food Vol.18 No.12

Stamens of Nelumbo nucifera Gaertn have been used as a Chinese medicine due to its antioxidant, hypoglycemic, and antiatherogenic activity. However, the effects of kaempferol, a main component of N. nucifera, on obesity are not fully understood. We examined the effect of kaempferol on adipogenesis and fatty acid oxidation signaling pathways in 3T3-L1 adipocytes. Kaempferol reduced cytoplasmic triglyceride (TG) accumulation in dose and time-dependent manners during adipocyte differentiation. Accumulation of TG was rapidly reversed by retrieving kaempferol treatment. Kaempferol broadly decreased mRNA or protein levels of adipogenic transcription factors and their target genes related to lipid accumulation. Kaempferol also suppressed glucose uptake and glucose transporter GLUT4 mRNA expression in adipocytes. Furthermore, protein docking simulation suggests that Kaempferol can directly bind to and activate peroxisome proliferatoractivated receptor (PPAR)-α by forming hydrophobic interactions with VAL324, THR279, and LEU321 residues of PPARα. The binding affinity was higher than a well-known PPARα agonist fenofibrate. Consistently, mRNA expression levels of PPARα target genes were increased. Our study indicates while kaempferol inhibits lipogenic transcription factors and lipid accumulation, it may bind to PPARα and stimulate fatty acid oxidation signaling in adipocytes.

미만성 스텐트 내 재협착 병변에 대한 근접 방사선 치료 효과에 대한 혈관 내 초음파 장기추적 검사 소견

이봉기,홍명기,이명준,김성두,이세환,박창범,양태현,김민규,이승환,김영학,오승준,문대혁,이철환,김재중,박성욱,박승정 대한심장학회 2004 Korean Circulation Journal Vol.34 No.9

Background and Objectives:The long-term effects of β-irradiation on intimal hyperplasia (IH) within thestented segment and vessel, and the lumen dimensions of non-stented adjacent segments, have not beensufficiently evaluated in patients with ISR. The long-term (24 months) effects of β-irradiation (188Re-MAG3-filled balloon) were evaluated using intravascular ultrasound (IVUS) in patients with in-stent restenosis (ISR).Subjects and Methods:A two-year follow-up IVUS was performed in 30 patients with patent ISR segments atthe 6-monthly follow-up angiography. Serial IVUS images were acquired at 5 equidistant intra-stent sites and3 different reference segment sites (1, 2 and 4 mm from stent margin). Results:The mean intra-stent IH areaand IH burden significantly increased between 6 and 24 months-from 2.1±1.1 to 2.6±1.4 mm2 (p<0.001) andfrom 26±10 to 33±14% (p<0.001), respectively. There were significant decreases in the mean externalelastic membrane (from 10.1±3.9 to 9.7±3.9 mm2, p=0.015) and lumen area (from 5.6±2.3 to 5.1±2.3mm2,p=0.021) within the distal reference segments between 6 and 24 months. Target lesion revascularization (TLR)was performed between 6 and 24 months in 6 patients (20%) following the β-irradiation therapy. There wereno significant differences between the TLR and non-TLR groups, with the exception of a smaller minimumlumen CSA at 24 months in the TLR group. Conclusion:Because of a small amount of late loss between 6 and24 months, most irradiated ISR vessel segments remained stable for up to 2 years. However, quantitativeevidence of late catch-up was evident in most patients and was significantly associated with 24-month TLRin some patients with a smaller minimum lumen area. 배경 및 목적:스텐트내 재협착 환자들에서 베타 방사선 조사가 스텐트 내 분절의 내막증식(intimal hyperplasia, IH) 및 비스텐트 인접 분절의 내강구경에 미치는 장기적 효과는충분히 평가되지 않은 상태이다. 본 연구는 혈관 내 초음파 검사(Intravascular ultrasound, IVUS)를 이용하여스텐트 내 재협착(in-stent restenosis, ISR) 환자들에서 188Re-MAG3 충만풍선을 사용한 베타 방사선 조사의 장기적(24개월) 효과를 평가하고자 하였다.방 법:6개월 추적 관동맥 조영술 상 스텐트 내 재협착 분절이 개통 상태인 30명의 환자들에서 2년 추적 IVUS 검사를 시행하였다. 일련의 IVUS 영상들은 스텐트 내부의 5등분 등거리 위치 및 세 곳의 다른 참조분절에서 획득하였다. 증식내막 부하도(%)는 100×(증식내막면적/스텐트 단면적)으로 하였다. 결 과: 평균 스텐트 내 증식내막 단면적 및 증식내막 부하도 는 6개월에서 24개월 사이에 각각 2.1±1.1에서 2.6± 1.4 mm2(p<0.001) 및 26±10에서 33±14%(p<0.001) 로 유의하게 증가 하였다. 6에서 24개월 사이에 원위부 참조혈관들의 평균 외탄력막층 단면적과(10.1±3.9에 서 9.7±3.9 mm2, p=0.015) 내강 단면적은(5.6±2.3 에서 5.1±2.3 mm2, p=0.021) 유의하게 감소하였다. 표적 병변 재개통술(target lesion revascularization, TLR)은 베타 방사선 요법 후 6개월에서 24개월의 기간 동안 6명의(20%) 환자들에서 시행되었다. TLR군에서 24개월째에 최소내강 단면적이 작았다는 것을 제외하고는 TLR군과 non-TLR군 사이에 유의한 차이는 없었다. 결 론: 6개월에서 24개월 사이의 지연성 손실량이 적으므로, 방사선이 조사된 대부분의 스텐트 내 재협착 분절들은 2 년 동안 안정적이었다. 하지만, 대부분의 환자들에서 지 연성 추격의 정량적 증거가 존재했으며, 이는 일부 환자 들에서 24개월 내의 표적병변 재개통과 연관되었다.

배나무 무인 방제기의 개발을 위한 살포 시스템 설계

이봉기,민병로,이민영,화윤일,최동성,홍준택,이대원 (사) 한국생물환경조절학회 2013 시설원예‧식물공장 Vol.22 No.4

A remote controlled sprayer has designed, manufactured and experimented to spray well on pear trees with pesticides. This study was executed to automate pest management of pear trees. Types of spray nozzle, which was used on the system, were analyzed experimentally to find an optimal spray equipment configuration with several nozzles. Attributions of ultrasonic sensors were analyzed to adjust spraying distance of an unmanned sprayer system. This paper investigated shapes of pear trees and cultivating environment of pear orchard. In order to select optimal spray environment, liquid distribution was measured while angle of nozzle was changed. Additionally, liquid distribution by distance and sprayed liquid capacity by side distance were measured. According to information of shapes of pear trees and cultivating environment of pear orchard, sprayer frames of an unmanned sprayer system were manufactured and sprayer frames were suitable for interval of pear trees. The sprayer system could adjust width of sprayer frames to 2.5 m and height of sprayer frames to 1.7 m. Optimal angle of nozzle, and optimal distance between objects and nozzle were 15˚ and 0.8 m. When side distance was placed from 1.2 m to 1.8 m, sprayed capacity reached to the highest amount. 배나무 방제용 무인살포시스템 개발을 위하여 생력화를 위한 작업기기를 설계하였다. 또한, 노즐의 분무유형을 실험적으로 분석하여 적정 살포를 위한 노즐 각도,노즐과의 거리, 수평방향 살포시 거리를 선정하였다. 본연구를 수행하기 위하여 배의 과수 형태와 재배 환경을사전 조사하였다. 살포시스템의 살포진행방향에 적합한분사 노즐각도를 선정하였다. 배나무와 살포시스템 간의수직거리에 따라 달라지는 살포 정도를 비교하기 위하여노즐과의 높이에 따른 분포도를 측정하였다. 배나무와살포 시스템과의 적정 측면 거리를 선정하기 위하여 측면 살포시 거리에 따라 달라지는 분무량을 측정하였다. 무인살포시스템의 약대는 배의 식재 간격에 적합하도록 좌우가 동일한 형태로 2.5m까지 펼쳐지도록 설계 및제작 하였다. 또한 일정하지 않은 배나무의 높이에 따라약대의 높이가 1.7m까지 조절되도록 하였다. 본 시스템에 적합한 노즐 각도는 15˚로 나타났다. 배나무와 살포시스템과의 수직거리는 0.7m에서 0.9m의 간격을 유지하여 약제를 살포해야 된다는 것을 알 수 있었다. 수평방향으로 살포하는 경우 좌우 −0.9m에서 0.9m까지의 분무량이 가장 많았다. 약대와의 거리가 0.9m에서 2.1m 일 때 가장 많은 분무량을 나타냈다. 실험을 통하여 배 과수원에서의 무인살포시스템에 맞는분무 환경을 확인 할 수 있었다. 배 과수와의 거리에 따라적정 거리를 유지하는 시스템을 개발함으로써 효율적인약액 살포가 가능하게 하였다. 하지만 본 연구에서 진행된실험은 제한된 실내 환경에서 진행된 것이기 때문에 제작된 시스템의 실제 과수원 환경에서의 실험이 필요하다.

Phosphodiesterase 억제제인 IBMX의 국소투여가 흰쥐의 경동맥 손상 후 신내막증식에 미치는 영향

이봉기,윤정한,이한효,김장영,고지연,이승환,유병수,최경훈,황성오 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.10

Comparison of Age of Onset and Frequency of Diabetic Complications in the Very Elderly Patients with Type 2 Diabetes

이봉기,김상욱,최대희,조은희 대한내분비학회 2016 Endocrinology and metabolism Vol.31 No.3

Background: The prevalence of type 2 diabetes in elderly people has increased dramatically in the last few decades. This study wasdesigned to clarify the clinical characteristics of type 2 diabetes in patients aged ≥80 years according to age of onset. Methods: We reviewed the medical records of 289 patients aged ≥80 years with type 2 diabetes at the outpatient diabetes clinics ofKangwon National University Hospital from September 2010 to June 2014. We divided the patients into middle-age-onset diabetes(onset before 65 years of age) and elderly-onset diabetes (onset at 65+ years of age). Results: There were 141 male and 148 female patients. The patients had a mean age of 83.2±2.9 years and the mean duration of diabeteswas 14.3±10.4 years. One hundred and ninety-nine patients had elderly-onset diabetes. The patients with elderly-onset diabeteshad a significantly lower frequency of diabetic retinopathy and nephropathy, lower serum creatinine levels, lower glycated hemoglobin(HbA1c) levels, and similar coronary revascularization and cerebral infarction rates compared to those with middle-age-onsetdiabetes. There was no frequency difference in coronary revascularization and cerebral infarction and HbA1c levels between threesubgroups (<5, 5 to 15, and ≥15 years) of diabetes duration in elderly onset diabetes. However, both in the elderly onset diabetesand middle-age-onset diabetes, the cumulative incidence of retinopathy was increasing rapidly according to the duration of diabetes. Conclusion: We report that individuals with elderly-onset diabetes have a lower frequency of diabetic retinopathy and nephropathyand similar cardiovascular complications compared to those with middle-age-onset diabetes.

Leptospira(Korea)의 병원성 및 leptospirosis 환자 조직과의 특이성

이봉기,유주현,이태윤,박전한,이원영,김주덕 한국미생물학회 1985 미생물학회지 Vol.23 No.4

유행성 출혈형 폐염양 환자로부터 분리한 병원체에 대한 환자 항 혈청의 조사와 동물의 감염성 및 이 질환에 의해 사망된 환자의 조직내 균체검사의 결과는 다음과 같다. 1) 분리균에 대한환자의 항 혈청검사에서 42명 중 39명이 항체역가 1 : 40이상의 양성반응으로 나타났다. 2) 균접종에 대한 동물의 감수성 검사에서 guinea-pig은 LD가 $1-2{\times}10^9$ 균수인데 반하여 mouse에서는 LD가$1-2{\times}10^9$ 균수 이상으로 감수성이 낮고, 다람쥐는 거의 저항성으로 나타났다. 감염동물에서는 굵은 5 -10일경 간장, 폐장, 신장, 혈액 및 뇨에서 모두 검출되었다. 감염된 장기의 병리적 소견에서 폐장에는 폐포내 심한 출혈과 단핵백혈구의 침윤 및 기관지 폐염을 나타내고, 간장에는 Kupffer cell외 과다증식, 동양구조내 울혈 및 저산소증 변화, 국소적 허혈성 괴사를 볼 수 있고, 신장의 경우 단 수질내 출혈과 뇨에서는 많은 균과 적혈구를 관찰할 수 있었다. 3)균에 대한 특이 가토 항 혈청은 환자의 항혈청에서와 같이 간접 면역 형광법에 의해 유행성 출혈열 폐염양 질환으로 사망한 환자의 조직내 감염군과 강하게 반응하였다. Leptospira isolated from patients and natural paddy water were further studied to confirm their serologic specificity with the bacteria in infected animal tissue and autopsied tissue of patients died with leptospirosis. And pathologic patterns of the inoculated antimal and the virulence of the bacteria in the animals were also studied. The findings are summarized as follows; $LD_{50}$ dose of the bacteria in guinea-pig were $1-2{\times}10^9$ cells and mice were found to be susceptible to them even though the degree of susceptibilities were much inferior to guinea pig. The bacteria were recovered from various organs; demonstrated massive hemorrages due to diapedesis and monocyte infiltration were observed, in some cases, intramedullary hemorrages of the infected kidnies and hematuria were recognized. All of the hyperimmune sera were strongly reacted with the tissues from autopsied human case who died of EPHF(Epidemic Pulmonary Hemorrhagic Fever) in immunofluorescent antibody tests.

A simple fabrication and integration technique of microlens for microfluidic lab-on-a-chip by overflow of UV resin through holes

이봉기,박장민,김동성,Tai Hun Kwon 한국물리학회 2011 Current Applied Physics Vol.11 No.3

In the present study, a simple fabrication technique for microlens or microlens array is proposed based on an overflow of a UV curable resin through micro-holes followed by photopolymerization of the resin. As a first step of the present technique, a micro-hole is precisely drilled on a flat plastic sheet. A UV curable resin is carefully spread over another plastic sheet, and then an overflow process is carried out by compressing the spread resin with the holed sheet. The overflowed resin through the hole is then cured by irradiation with UV light and consequently, the microlens is formed from the overflowed resin on the holed sheet. By utilizing the present fabrication technique, microlenses of 600 and 750 mm in diameter were successfully manufactured. The fabricated microlens was also characterized by measuring its detailed dimensions and focal length. The microlens of 750 mm in diameter showed a smooth convex surface and the focal length of 2.11 mm.

Lymphokines and Cytotoxic Lymphocytes

이봉기 연세대학교 의과대학 1986 연세의대논문집 Vol.19 No.1

동일독일연구 : 화폐통합시 동서독 모두 사기행위 만연 -신탁관리청의 설립과 동독국영기업을 둘러싼 부정행위 (하)

이봉기 평화문제연구소 1997 통일한국 Vol.162 No.-

통일대비 : 통일독일연구 ; 야심찬 작센주, 우울한 작센안할트 -구동독지역의 경제전환과정을 중심으로-

이봉기 평화문제연구소 1996 통일한국 Vol.146 No.-